• 한국시스템다이내믹스연구
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• 제6권1호
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• pp.5-15
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• 2005

This paper investigates psychological differences between constructors and interpreters of causal maps. This paper argues that dissipation effects and dilution effects applies to those who are to interpret causal maps not to those who construct them. Dissipation effects are psychological tendency that people perceive causal effect as weak as the number of causal links increases. Dilution effects occur when people undervalue the strength of causal relation as the number of causal variables increases. Experimental results show that concentration effects opposite to the dissipation effects and dilution effects explain more correctly the perception of constructors of causal maps. This paper points out that this asymmetric psychological tendencies between constructors and interpreters of causal maps is the psychological source of the communication problems between systems thinkers and their clients.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제45회 KOSCO SYMPOSIUM 초록집
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• pp.61-62
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• 2012

The present study has numerically investigated the effects of fuel-side dilution and pressure on flame structure and extinction scalar dissipation rate of turbulent syngas nonpremixedd flames. Numerical results indicate that for highly diluted case, peak temperature is decreased and stoichiometric mixture fraction is increased. By decreasing the pressure and the nitrgen dilution levelcreased, the extinction scalar dissipation rate is increased.

• 대한기계학회논문집B
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• 제27권5호
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• pp.596-603
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• 2003

Present study has been conducted to see the relative effects of adding N: to fuel-side and air-side on flame structure, soot formation and NOx emissions. Experiments were carried out to ascertain to what degree chemical kinetics and/or molecular transport effects can explain the differences in soot formation and NOx emission by studying laminar diffusion flames. Direct photograph was taken to see the flame structure. CARS techniques was used to get the flame temperature profiles. And spatial distribution of soot could be obtained by PLII method. CHEMKIN code was also used to estimate the global residence time to predict NOx emissions at each condition. Results from these studies indicate that fuel-side dilution is more effective than air-side dilution in view of NOx emissions. However, air-side dilution shows greater effectiveness over fuel-side dilution in soot formation. And turbulent mixing and heat transfer problems were thought to be considered in practical applications.

• 한국의류학회지
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• 제35권1호
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• pp.63-76
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• 2011

The potential for brand dilution occurs when new brands merge with an identical image of a parent brand. Despite the significant attention regarding the effects of dilution on brand extension, there is limited research on brand dilution in the beauty industry. This study analyzes the effect of the typicality of extensional type on brand attitude or purchase intention for potential dilution toward beauty brand extension. In addition, we examine the moderating effect of knowledge transfer when customers evaluate the typicality of the extensional type for potential dilution toward beauty brand extensions. For the experiment, 4 description type factorial designs were performed. A total of 219 students participated in the experiment who had experience of visiting a beauty salon. The results are as follows. First, there are significant independent and interaction effects between the typicality and extensional type that reveals differential influences on the attitude or purchase intentions toward extended beauty brands. Second, the knowledge of the parent brand is transferred to extended brands. Third, there is a significant moderating effect of knowledge transfer, as customers evaluate the typicality of the extensional type for the potential dilution toward beauty brand extension. This study provides some theoretical and practical perspectives with some limitations.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
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• pp.73-76
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• 2013

The inert gas dilution effect for the stability of a stratified propane premixed flame has been experimentally studied. The addition of inert gases to a stratified premixed flame, which used to be very stable without dilution, makes a flame unstable. The lower equivalence ratio on the outer premixed flame and the lower fuel flow rate through the inner nozzle were observed to be the more stable conditions for the stratified premixed flame with nitrogen or argon dilution. It has been interpreted with the flame structure change such as shift of stoichiometric ratio region in a flame.

• 한국임상수의학회지
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• 제35권2호
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• pp.39-45
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• 2018

We evaluated the effects of green tea extract (GTE) supplementation at different dilution steps on boar sperm freezing and in vitro fertilization. Sperm intracellular hydrogen peroxide ($H_2O_2$), motility, viability, acrosome integrity and morphology were determined. In addition, sperm IVF parameters (penetration and monospermy) and glutathione (GSH) levels of presumptive zygotes (PZs) were evaluated. Semen was diluted in lactose egg yolk (LEY) and cooled at $5^{\circ}C$ for 3 h (first dilution step) and then diluted in LEY with 9% glycerol and maintained at $5^{\circ}C$ for 30 min (second dilution step). Four experimental groups were compared: first and second dilution steps without GTE (control), first dilution step with GTE (Step 1), second dilution step with GTE (Step 2) and first and second dilution step with GTE (Step 1+2). The spermatozoa were frozen in nitrogen vapor. Higher sperm motility, viability and acrosome integrity after thawing were observed in Step 1, Step 2 and Step 1+2 groups compared with the control (P < 0.05). Lower $H_2O_2$ level was observed in Step 1+2 compared with control and Step 1 (P < 0.05). For IVF, matured oocytes were co-cultured with spermatozoa frozen according to the experimental groups. GSH levels of PZs were significantly higher in Step 2 and Step 1+2 than in control and Step 1 (P < 0.05) without a significant difference in IVF parameters. In conclusion, supplementation with GTE in both first and second dilution steps during the freezing process resulted in better boar sperm cryopreservation and might be beneficial for further embryo development.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제45회 KOSCO SYMPOSIUM 초록집
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• pp.63-64
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• 2012

The present study has numerically investigated the effects of the fuel-side nitrogen dilution on the precise structure and NOx formation characteristics of the turbulent syngas nonpremixed flames. Numerical results indicate that for highly diluted case, the flame structure is dominantly influenced by the turbulence-chemistry interaction and marginally modified by the radiation effect. On the other hand, no-dilution case with the longer flight time and the relatively intermediate scalar dissipation rate is influenced strongly by the radiative cooling as well as moderately by the turbulence-chemistry interaction.

• 한국환경보건학회지
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• 제22권3호
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• pp.98-102
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• 1996

This study investigated performance of the phenol degradation and reaction characteristics according to variation of phenol volumetric loading rates and dilution rates in suspension and PACT reactors using Pseudomonas sp. B3. 1. Removal efficiencies of the PAC unit indicated about 100 % with phenol volumetric loading rates from 0.4 phenol $kg/ma^3\cdot d$ to 1.2 phenol $kg/m^3\cdot d$, however, which of the suspension reactor showed about 100% with from 0.2 phenol $kg/m^3\cdot d$ to 0.75 phenol $kg/ma^3\cdot day$. 2. The cell density slightly was decreased from 298.2 mg/l to 272 mg/l, when dilution rate for suspension was reactor increased from 0.4 to 1.41 1/d, and also the cell density suddenly was decreased to 145.5 mg/l and was washed out at the dilution rate higher than 1.60 1/d. But the cell density for the PAC unit was linearly decreased with dilution rate of from 0.8 to 3.0 1/d, and showed 220.75 mg/l at maximum dilution rate. 3. The phenol utilization rate was increased from 0.008 to 0.031 phenol g/l$\cdot$h, when dilution rate for suspension reactor was increased from 0.4 to 1.5 1/d, however, the rate for the PAC unit was linearly increased from 0.017 to 0.061 phenol g/l$\cdot$h as variation changes from 0.017 to 0.061 phenol g/l$\cdot$h dilution rate.

• Water Engineering Research
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• 제3권2호
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• pp.93-111
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• 2002

In this paper, mixing characteristics and dilution of the merging buoyant discharges from array of multiple jets has been extensively studied in the hydraulic model experiments. New equations for dilution, which include the merging effects correctly, were derived. Experiments were constructed in a 20-m long, 4.9-m wide and 0.6-m deep flume, and the model diffuser was manufactured to indicate the typical characteristics of the existing ocean wastewater outfall in South Korea. Buoyant discharge from the diffuser was reproduced using heated water. Water temperature was measured using CC-Type thermocouple sensors, which were connected to a 40-channel data logger. Experimental results show that merging between ports in a particular riser is dependent upon the discharge densimetric Froude number, whereas merging between two ports which are facing each other at 90$\circ$ at the adjacent risers is dependent upon the discharge densimetric Froude number and distance from the port and port spacing. Centerline dilution increase with distance from the port outlet until two plumes has merged. However, after merging occurs, increase of the centerline dilution almost stops. Further distance from the position where merging occurs, centerline dilution increases again.

• 대한기계학회논문집B
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• 제28권1호
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• pp.1-8
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• 2004

An study has been performed with axisymmetric coflow diffusion flames to investigate the influence of air-side fuel side dilution and initial preheated temperature on the soot formation in methan/air flames. Soot quantities are determined by using PLII(Planar Laser Induced Incandescence), such a $C_2$H$_2$ major species(CH$_4$, $O_2$, $N_2$) and temperature are simulated by chemkin code. The numerical analysis was performed with transport properties and detailed reaction mechanisms m axisymmetric coflow diffusion flames. The study of how flame temperature and $N_2$ dilution of air and fuel side influence the soot concentrations is focused. Soot concentrations results on PLII show that preheated temperature contributes to an increase in the soot volume fraction, and soot formation Is more productive to air side dilution than to fuel side dilution. $C_2$H$_2$ concentrations have a similar tendency to soot concentrations.